Contactor-commutator for dynamo-electric machines.



H. R. RIVERS-MOORE & J. MoL. DONALD. CONTACTOR GOMMUTATOR FOR DYNAMO ELECTRIC MACHINES. APPLICATION FILED 001a 1907.

917,898. I Patented Apr. 13', 1909.

INVENTORS:

Fig.5. WITNESSES mg commutator segments.

are rounded on their leading edges as at f UNITED STATES PATENT OFFICE.

HENRY RIVERS RIVERS-MOORE AND JOHN Mc-LEOD DONALD, OF LONDON,ENGLAND.

.CONTAGTOR COMMUTATOR FOR DYNAMO-ELECTRIC MA GIHNES.

Qpecification of Letters Patent.

Patented April 13, 1909.

Application filed 0ctober 5,-1907. Serial No. 369.088.

To all it may concern:

Be it known that-we, HENRY- Rrvsns- RIVERS-MOORE, of 37' Kempsford Gardens, Earls Court, London, England, engineer, and JOHN MoLnoD DoNALn, of 49 Shepherds Bush road, London, England, engiheen-have invented a certain new and useful Contactor- Commutator for Dynamo-Electric Machines,

"hitherto possib In the accompanying diagrammatic drawmgs :Figure 1 is an end view of one form of arrangement in accordance with this invention, showing for the sake of example a machine with an external stationary armature and rotating field; Fig. 2 is asection online A-A, Fig. 1, and showing. the means for supporting the pivots of the movable contactors and for I returning the contactors when the same a detail end ofthe contactor return springs. Figfi isan end view of the apparatus seen from the right of Fig. 2, with the contactor supporting ring removed.

a are and b are the contactors each pivoted, as 'at c in a series of brackets c atand returnsprfngs tached at intervals around a ring 0 fixed to any suitable part of the machine. Each of said contactors corresponds to one commutator segment. The contactors b are normally held out of contact with the segmentsa.....bythep1illofspringsb.... secured to bent pins b fixed to the ring a. s

d d are cams securedto the shaft e and 7 adapted to rotate therewith so as to operate on the contactors b successively to make contact with the commutator seg-- ments (1..... The cams d d are so arranged that each always holds two or more contactors in contact with their correspond- The cams d (1 against other blow-out.

e released. Fig. 2 being.

the commutator segments,

and sharp on their rear edges as at gin order that the contactors b may be gradually and smoothly brought into contact with the commutator segments and suddenly released therefrom by the. springs b to eiiect a rapid and direct break.

h h are collectors establishing connection between the pivoted ends of the contactors and sli rings 1' j from which the current is finally ed by means of brushes. The collectors h h rotate with the cams d d and make connection with a greater number of contactors than are actually in contact w th commutator segments. In this manner the collectors make and break contact only with contactors which are dead.

By the use of an arrangement in accordance with this invention, better insulation of the commutator segments may be provided than is possiblein the ordinary construction where the surface of the commutator must be smooth. By means ofthis possibility of improved insulation and by absence of sliding brushes on the commutator, flashing over can'be eliminatedand high voltage er segment/is rendered possible. The quick break obtained by the use of contactors also tends to reduce inductive s arking, which may be further diminished y magnetic or By means of this invention a stationary armature may be employed without having a complicated rotating brush. gear, and the benefit of having a stationary armature'for high voltage machines requiring high insulation is well known. a

It will be understood that if the construction is such that the commutator rotates, the cams d are stationary, this being an inversionof the present construction.

Whatwe claim, and desire to secure by Letters Patent, is:

1. Apparatus'for taking ofl current from the armaturesof d amoelectric machines, comprising in'com 'ination with contactors movable relatively to the commutator segments,- means for -moving' the contactors gradually a ainst the commutator segments and means or rapidly returning them out of contact therewith. I

2. Apparatus for taking ofi current from the armatures of d amo electric machines, comprising in com inat'ion contactors movable relatively to the commutator segments, a rota member. adaptedin its rotation to move t e contactors gradually against said segments, and means for-rapidly returning In witness whereof, we have hereunto" signed our names in the presence of two subscribing wltness'es.

HENRY RIVERS RiVERS-MOORE. 'JOHN MGLEOD DONALD.

Witnesses to the signature of Henry Rivers Rivers-Moore GORDON MELVILLE CLARK, ALFRED BEESLEY CAMPBELL. Witnesses to the signature of John McLeod Donald: 7

' RLSWIRE GRIFFITHS, 1

O. M. ELLrs. 

